Joe’s Weather Blog: Here comes more snow (MON-1/18)
Good morning…it’s cold out there. The lowest temperature I could find this morning was -11° in Maryville, MO and -10° in St Joe and Tarkio, MO. Officially KC dropped to -3° yesterday before midnight and again down to -3° this morning before sunrise. This was the coldest morning since last JAN 7th and 8th when interestingly we dropped to -3°. The focus on today’s weather blog is on the snow scenario…it’s another tough forecast because some things are lining up but the length of the snowfall + a few “gotchas” showing up in the model data today suggest we’ll have to watch this one very closely tomorrow afternoon as the snow bands are trying to come together.
Forecast: (9PM Update)
Tonight: Increasing clouds with pretty steady temperatures. Lows 15-20°
Tuesday: Becoming more and more cloudy with snow developing in the afternoon into the evening hours. Bands of snow will set up in parts of the region producing some heavier snow areas. Where these bands precisely set up though is impossible to predict. Where they are a bit more persistent though will be the areas that have the most snow…upwards of 4″. Where the bands struggle the most or don’t set up at all in a coherent way will reduce the overall snow amounts to perhaps 1″.
Wednesday: Variable clouds and cold with highs in the 20s.
Discussion: (9PM Update)
I haven’t seen anything in the latest data to say that the forecast needs revisiting at this point. This is simply not the greatest set-up for snow around these parts. There are a few issues with the set-up tomorrow that still bother me quite a bit, especially on the south side of the metro in terms of how much snow will actually fall. The good news for snow lovers is that we’re still seeing about 2/10″ liquid equivalent being spit out by the latest NAM model with about 50-75% of that on the latest hi-res NAM output which may be a better way to go. That particular model is showing these roughly 1 county wide areas of heavier amounts however…again where those precisely set up won’t be know till the event gets well underway tomorrow. So there is some upside to the 1-3″ average from KC northwards in localized areas. South of 435-470 south though I’m not too overly impressed by what I’m seeing as I think the issue is that the mid levels part of the atmosphere is showing the best moisture (where the snowflakes form) to be rather limited or just not as persistent as what could happen about 50 miles farther northwards.
As far as any other type of precip (i.e. freezing drizzle/sleet)…I’m not too excited about the mantra about that cutting into the snow totals…IF we end up with some freezing mist/drizzle it will be a sign of a storm that doesn’t have enough moisture in the mid levels to create snow at that point in time. There will be no connection between the freezing mist/drizzle cutting into snow totals…IF that is the case then the snow totals were not going to work out for your local area…if that makes sense.
For timing this really should wind down towards 9PM for the KC metro area it appears. I still have concerns about the PM rush. There may be a few bands of snow that are temporary setting up around lunchtime or so.
Overall I think 1-3″ is still a good forecast as an average through the KC metro (my opinion). Some may do a bit better (odds favor north of the KC metro area) while others may really struggle to get more than 1″ (especially farther south of JOCO/JACO line.
More if necessary later this evening.
Back to the previous entry…
I’ve been watching the data for the past couple of days for the NE part of the country where the model data mostly has been rather consistent in predicating a significant blizzard to hit the Mid-Atlantic states through the coastal areas of the northeast. Some of the snow forecasts the model is spitting out are impressive…in the 12-24″ range and combined with 50 MPH winds, is an all out close down the NE part of the country type of blizzard. It will happen over the weekend so that may minimize impacts in a sense but it’s impressive eye candy for a meteorologist 4+ days away. The consistency is what’s been interesting about this…
I bring all this up because it seems we’re dealing with the table scraps this winter in KC with snow. Granted the system on early on Sunday morning over-produced for some…that was mostly a function of the powdery nature of the snow meaning the snow ratios where through the roof for this part of the country. Overall though that was a dusting to 3″ event…and the one later tomorrow may be somewhat close to that in KC as well…again table scraps compared to what’s potentially ahead in other parts of the US.
So the scraps heading our way later tomorrow though could pose their own set of issues. Granted there is now plenty of treatment on the roads, so that is a positive. The timing of the snow though again is a bit of a concern since we’re talking close to evening rush hour Tuesday. Bands of light to moderate snow moving through in the late afternoon/evening can create some serious traffic headaches in KC and that will need to be watched for. I can’t promise the entire metro will have a rougher late rush hour Tuesday but I wouldn’t be surprised to see parts of the metro having a tougher than usual time with the snow and the traffic tomorrow afternoon.
Data today shows the same things that Ii talked about yesterday on the air. I’m still not thrilled with the set-up to this. There are mismatched features in the upper levels of the atmosphere that are giving me consternation right now. One of which is the potential that the mid level moisture in the atmosphere may be a better factor north of KC than from KC southwards, reducing potential accumulations. There are signs that we could improve that aspect of the storm (briefly) in the mid-late evening Tuesday helping the snow cause a little.
This all affects the amounts of precipitation expected. Forecasting these amounts are usually the hardest part of the models job…and when they are way off, one way or the other, you can get some rather large model busts it what happens on the ground. I like using this data, then converting the liquid amounts to snow and figuring out the forecast. So where are we with that data…
The NAM model…
The hi-res NAM model
the GFS model
and finally the Canadian model…
So by looking at the data above…it seems there is a pretty coherent signal for liquid equivalent amounts of 1/10-1/4″ on average with all the model data. The GFS is somewhat more aggressive on the north side of KC and the Canadian is towards St Joe and the 36 highway corridor area. This is the models way of trying to “sniff out” some of these heavier snow bands that may try and set up somewhere between KC and the MO/IA border.
Now the snow ratios won’t be to the extreme as what happened on Suday early morning. we were getting 25-30:1 ratios there with the bitterly cold air. Later Tuesday the air won’t be nearly that cold, not at the surface nor aloft so the snow ratios will be more typical. It shouldn’t be a dry and sugary type snow like the other morning…it will be more of a “wetter” more pack-able type snow (the kids should be happy at least). Factoring in this information leads one to think that IF we get the forecasted liquid equivalents the the proper snowfall forecast is roughly on average 1-3″ or so…with the potential of some 4″+ where ever those unforecastable (in this scenario) heavier bands try and set up. I’m leaning towards those heavier bands setting up towards the north of KC and northeast of the KC metro area at this point.
We still need to watch another system developing nearby on THU…that is what’s going to turn into the potential NE part of the country blizzard this weekend. Should things come together that may be worth another 1-3″ or so event around these parts…but again let’s deal with one system at a time.
That’s it for today…another update comes out tomorrow unless something significant changes in the data later this afternoon.